94 355 LT1/LT4 with 95 vented opti, 95 timing cover and Cloyes billet adjustable timing chain set.

If I retard the cam 4 degrees, will the computer somehow compensate and adjust for it?

I know that it does not have the front mounted crank position sensor that the 96-97s have.

I cannot find anything in my service manual that shows a crank or cam position sensor.

 

No, the computer will not compensate. You would have to do that with programming or the new MSD opti has some adjustment for that. Cam and crank position are determined by the opti. Most people don't/need to use an adjustable timing set on an LT1.